Madison CJ, Melson RA, Conlin MJ, et al. - This retrospective analysis was performed among United States Veterans with lung cancer, to determine how chemotherapy and immunotherapy could impact thromboembolic risk in these patients during the first 6 months (180 days) post-initiation of systemic therapy. Treatment with common front-line agents was received by these patients, and four groups were defined: chemotherapy alone, immunotherapy alone, combination of chemo- and immunotherapies, and molecularly targeted therapies (control group). In this cohort, overall incidence of thrombosis was 7·4%, and significantly different rates were observed among the different groups. By exploring models including multiple confounding variables as well as the competing risk of death, an elevated incidence of thrombosis was found in relation to both chemo- and immunotherapies, either alone or combined, vs the control group. Findings, thus, showed that use of anticoagulation was associated with risk of thrombosis, accounting for various confounders, including history of thrombosis.